If you own one of these NEC PowerMates your hinge has probably broken out of the plastic standoffs. I decided to create a replacement bracket and do preventative steps to prolong the life of the new hinge.
Disassembly
There are two screws under the display cover. Remove them and slide the cover off. Remove the screws holding the display to the hinges and remove the screws on the back of the display frame (if not broken already)
Now remove the bracket holding the display cables and grounding points on the back of the frame and you should be able to remove the display (be careful with it)
The hinge with the massive spring puts a lot of strain on the plastics. I believe the grease is gummed up which is why I removed the C-clip on one side, slid the plastic part (holding the spring) off the metal part and cleaned and reapplied fresh grease.
It should be possible to turn the hinge with the small metal piece which attaches to the display by hand in one direction, and barely (it hurts) in the other. If you can't turn it at all it needs fresh grease. If you applied fresh grease use some pliers to work the grease in.
Repair
In my case, the standoffs were mostly broken off and the threaded inserts still attached to the screws holding the hinge. I drilled / cut / filed down the standoffs to about less than 1cm:
Print the two STL files (I used PETG with 80-100% infill) and insert the threaded inserts into the bracket. I set my soldering iron to 240 °C (same / similar temp as you would print the PETG model) and cycled through the four inserts, always inserting it 1-2mm before moving on to the next. I didn't want to stay too long on one insert to avoid deforming the bracket too much.
After that, insert the bracket into the cleaned up display frame and fill it up / glue it down with two component epoxy glue or your favourite product for such projects:
I let it harden overnight and reattached the display hinge (don't screw too hard otherwise the bracket will break and it will be a mess to get it out with the glue)
At this point my hinge was already functional but depending on the quality of the 3D print and the glue you might want to wait testing the display because there is a risk it will break off again.
Mount the computer part back on and you'll notice that there is a metal part above the hinge. Here is where you can put the second print to support the hinge. If your plastic standoffs are not too far gone, maybe this wedge is all you need but in my case it wasn't.
The author marked this model as their own original creation.